Method of and apparatus for cutting the teeth of gear-wheels.



R. REINECKER.

METHOD 0F AND APPARATUS FOR CUTTING THE TEETH 0F GEAR WHEELS.APPLICATION FILED sPT.22, 1914.

1,140,610. Patented May 25, 1915.

3 SHEETS-SHEET l.

I I L R. REINECKER.

METHOD 0F AND APPARATUS EUR CUTTING THE TEETH 0F GEAR WHEEL APPLICATIONFILED sEPT.22, 1914'.

1,14o61.oo T Patented MM5, 1915.

3 SHEETS-SHEET 2.

R. REINECKER. METHOD oF AND APPARATUS EoR CUTTING THE TEETH oF GEARWHEELS.

v iwf/WW f im H HR Patented Mw 25, 1915. y 3 SHEETS-SHEET 3.

UNITED sTATEs PATENT onirica.

RICHARD REINECKER, 0F CHEMNITZ, GERMANY.

METHOD 0F AND APPARATUS FOR CUTTING THE TEETH O GEAR-IHEELS.v

Specification of Letters Patent.

Patented May 25, 1915.

Application filed September 22, 1914. Serial No. 862,980.

T0 all 'whom it may concern:

Be it known that I, RICHARD REINECKER, a citizen of the German Empire,residing at Chemnitz, in the Kingdom of Saxony, Germany, have inventedcertain new and use'- ful Improvements in the Method of and Apparatusfor Cutting the Teeth of Gear- VVheels; and I do hereby declare thefollowing to be a full, clear, and exact description of the invention,such as will enable others skilled in the art to which it appertains tomake and use the same, reference being had to the accompanying drawings,and to letters or figures of reference marked thereon,

'which form a part of this specification.

My invention relates to improvements in the method of and apparatus forcutting the teeth of gear wheels such as spur gears and screw gears, andmore particularly in the method in which the teeth are cut by means ofmilling tool in the form of worms according to the involute principle.

In this method the milling tool is automatically shifted over the blankin the direction of the axis of the blank, and the milling tool isinclined relatively to the blank in such a way that the direction of itsthreads coincides with that of the teeth be-v ing cut on theiblank. Theblank must be rotated during the cutting operation, and this rotation isat a certain ratio relatively to the rotation of the blank, which ratiodepends on the number of the threads of the milling tool and the desirednumber of the teeth of the blank. The tool and the blank areoperativelyI connected with each other. If the rotation imparted to theblank corresponds to the number of the teeth being cut and the number ofthe threads of the tool, a spur gear is produced, and if the blank isrotated at a higher or lower speed, a gear wheel provided with curvedteeth, and more particularly a helical gear wheel is produced. In thisoperation only a part of the teeth of the milling tool is made use loffor cutting the teeth of the blank, and

from the beginning to the end of the operation the same teeth of themilling tool are operative, while the remaining teeth are not used.Therefore the teeth of the milling the blank i's not uniform, and theoperation of the gear wheel is inaccurate. This is particularly the caseif the tool must be exchanged several times while cutting a singlewheel.

The object of the present improvements is to provide a method and anapparatus in which this objection is removed.

With this object in view my invention consists in so operating the tooland blank relatively to each other that not always the same teeth of themilling tool are used for cutting the teeth'of the blank, but thatduring the cutting operation other parts of the milling tool come intocutting position, so

that the work is distributed over a large number of the teeth of themilling tool, and the whole blank can be cut in one operation withoutexchanging the tool. Thereby the cutting power and the life of the toolare materially increased.

In carrying out the invention I construct the machine in such a way thatan additional relative movement is imparted to the tool and the blank inthe direction of the axis of the tool apart from the movement of thetool in the direction of the teeth being cut. Preferably this additionalmovement is imparted to the tool, and its effect is that in the courseof the cutting operation always otherparts of the teeth of the tool comeinto cutting position. According to this axial displacement acorresponding additional rotary movement must be imparted to the blank,which additional rotary movement is entirely independent of the numberof the threads of the tool and the number of the teeth of the blankbeing cut. Thereforethe axial displacement of the tool and thecorresponding additional rotation of the blank can be use; l in themanufacture of spur gears aswell as in the manufacture of screw gearsmade according to the well known involute method.

For the purpose of explaining the invention an example embodying thesame has been shown in the accompanying drawings, in which the sameletters of reference have been used in all the views to indicatecorresponding parts.

' of an old machine of the class to which my invention relates, thetoolbeing shownl in two different positions, and the blank being shownin broken lines and in front of the tool, Fig. 2, is a similar viewshowing 'my improved machine, Figs. 3, and 3a,-are re-l spectively aside `view and a plan view of the tool acting on the blank forcutting-the teeth of a spur gear, the igures illustrating the oldmethod, Figs. 4 and 4, are similar views illustrating my improved methodwith reference to cutting the teeth of a spur gear, the parts beingshown in initial positions,

and Figs. 5 and 5a, are similar views showing the parts in the finalpositions.

Referring at first to Fig. 1 of the drawings, the milling tool 1 ismounted on a slide 2 which is vertically shiftable on a frame 3. Themilling tool 1 is movable in the direction. 4 4 of the axis ofthe blank5 along the path 6. The mechanism for imparting to the tool the saidmovements is known in v the left a distance indicated in Fig. 2 by thenumeral 8. A corresponding rotary movement is imparted to the blank 5.

In Figs. 3 and 3 I have shown the old method in a diagrammatical way,the tool being in initial position.

In Figs. 4 and 4a and 5 and 5 Ivhave shown the improved method, Figs. 4and 4a showing the parts in the initial positions andl my invention, `Ihave si 5 is rotated in the direction of the arrow 10.-

Corresponding parts of the blank and tool have been indicated by theletters a', b', c', d', e and 11,12, c, d, e.

I claim Vherein as my invention:

1. The herein described method of cutting the teeth of'spur gears orscrew gears, which consists in moving a helical cutting tool with itsthreads in th'e direction of the teeth being cut over the rimI of theblank in a direction parallel to the axis of the latter vwhile rotatingthe tool and the blank, and imparting axial displacement to the` tooland corresponding additional rotary movement to the blank.

2. In an apparatus of the class described, the combination with ahelical cutting tool, and a support for the blank, of means to impartrotary or cutting movement to the tool, means to impart relativeshifting movement to the tool and blank support in the direction of theaxis lof the blank placed on the support, means to rotate the blanksupport relatively to the tool, means to axially displace the tool'inthe direction of its axis, andv means yto impart additional rotarymovement to the blank support corresponding to the axial displacement ofthe tool.

In testimony that I claim the foregoing as I ed my name in presence oftwo subscribing witnesses.

RICHARD REINECKER.

